EFFECT OF γ-IRRADIATION ON THE CHEMICAL COMPOSITION AND ANTIOXIDANT PROPERTIES OF CUMIN EXTRACTS

ABSTRACT The effect of γ‐irradiation on the composition of cumin extracts and also their antioxidant properties were considered. The seeds before and after irradiation (10 and 25 kGy) were subjected to Clevenger extraction to obtain essential oils, and the constituents were identified by gas chromatography–mass spectrometry (GC/MS) analysis. In parallel, the hydroalcoholic extract was used for measuring flavonoid content, free‐radical scavenging (2,2‐diphenylpicrylhydrazyl assay) and antioxidant properties (β‐carotene bleaching test). The results of 10 fractions separated by GC/MS indicated that the total percentage was not affected by γ‐irradiation. γ‐irradiation of cumin seeds also resulted in a nonsignificant change in flavonoid content of the hydroalcoholic extracts. The antioxidant activities of both extract showed potent activities which were not further altered in irradiated samples. These data suggest that γ‐irradiation to cumin seeds is effective for maintaining the composition and antioxidant properties of the seeds. PRACTICAL APPLICATIONS Cumin is a traditional plant, originally cultivated in Iran and the Mediterranean region. Cumin is one of the most popular spices in the world widely used as a food flavoring agent. It is also used in Iranian traditional medicine for treatment of different diseases. Considering the contaminations of the seeds by microorganisms, their decontamination by γ‐irradiation seems to be useful. In this study, the compositions and antioxidant activities of the extracts derived from γ‐irradiated cumin seeds in comparison with nonirradiated ones will be achieved.